Human herpesvirus 8 (HHV-8): An immunofluorescence assay for latent HHV-8 antibodies revealed that U.S. homosexual men experienced an HHV-8 epidemic concurrent with the HIV epidemic in the early 1980s. HHV-8 infection was associated with numerous homosexual partners, and 35% of subjects with both HHV-8 and HIV developed Kaposi's sarcoma within 10 years. Five prototype assays for detection of HHV-8 antibodies were evaluated, and a combination of two (immunofluorescence for latent nuclear antibodies and enzyme immunoassay for antibodies against K8.1 recombinant protein) had particularly high sensitivity and specificity. Polyomaviruses: A study to examine reproducibility in detection of SV40 DNA in human mesothelioma or normal lung in nine laboratories was initiated. Hepatitis Viruses: Among subjects in the Multicenter Hemophilia Cohort Study, low levels of heterosexual transmission from men with hemophilia to their wives with hepatitis C virus (HCV) and hepatitis G virus (HGV). With HCV/HIV co-infection, atypical HCV antibody patterns were associated with an increased risk of end-stage liver disease. With HGV/HIV co-infection, AIDS risk was reduced 40% compared to HIV infection without HGV. In a case-control study in the Gambia of hepatocellular carcinoma associated with hepatitis B virus (HBV) and aflatoxin exposure, a technique was developed to detect the pathognomonic ser249 mutation of the p53 gene in plasma.